Insignia of Ebon Hold

Necro {1}(If a creature card with {1} in its mana cost
went to the graveyard from anywhere this turn, this
spell costs {1} less to cast.)
{b}, Pay 1 life, Sacrifice Insignia of Ebon Hold:
Search your library for a basic Swamp, Knight
card, or card with Necro, reveal it, put it in your
hand, and shuffle your library.